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Running fridge when on the road...
I've read several posts on this topic and I am wondering what you all do when you DO have a bunch of food in the fridge that needs to stay cold while driving? In my case, I feed my dogs a raw diet, so I need to keep raw meat cold.  Having to keep a cooler around for drives seems to defeat the purpose of having a vehicle with a fridge! Plus it takes up more room and would require getting ice.  Bah!

The other thing I'm wondering about is the dashboard switch that people have referenced. How do I know if I have one? Where do I look? And what, exactly, does the magic switch do? If i can't have the propane running while driving, what is the purpose of the switch?

Thanks!
1991 22' LD Multi-Plan
Re: Running fridge when on the road...
Reply #1 –
Is your fridge a 2-way or a 3-way, i.e. does it have a 12V mode? If it does, then a switch on the dash may enable that. Our '83 had a relay to switch 12V to the fridge when the motor was running. However, the fridge itself had to be switched manually to work on 12V. Our '04 has a 2-way fridge, but when driving, an inverter runs the fridge in AC mode. I have it set up also to switch automatically by a transfer relay. If someone installed such a system in yours, they may have a switch to enable it.

Steve
2004 FL
2013 Honda Fit
Re: Running fridge when on the road...
Reply #2 –
Lisa, I have a 87MP with the original 3 way fridge.  You may not have one or it could have been replaced by a 2 way fridge.  I do not know what year they stopped installing them.  3-way fridges will work on AC, DC, or Propane.  The 3 way fridge shifts automatically when turned on.  It will first pick AC - alternating current (electricity) if plugged in or if the generator (I don't have one) is running.  If no alternating current is available it will switch to propane provided the propane is turned on.  When there is no alternating current, no propane(turned off), driver key is on and switch on driver console turned on it will work on DC(house battery).  Running on DC(battery) it will take up more DC then the alternator can put out and will draw the house batteries down.  To keep from drawing down the house battery(DC) I have always run the fridge on propane when on the road as I boon dock often and want to have fully charged batteries when arriving at a campsite.  If running on propane remember to turn off the propane before filling the gas tank.  I have recently installed(this fall) a new cooling unit in this fridge and verified it does work all 3 ways.  Now as to which switch on the console it is I forget.  It is one of three switch on the driver console added aftermarket that I rarely use.  One is for the fridge, one for fog lights, and one for an extra fuel pump to prevent vapor lock.  I use the trial and error method to remember which does which. 

JohnF
2003 T/K and 1987MP w/roof sleeper(for sale this spring)
2003 TK
Re: Running fridge when on the road...
Reply #3 –
Thanks for the clarification. I don't think I have DC because the settings only show "AC" or "propane."

Why did they stop using the 3 way version? Seems like it would be more useful. Is it because it would drain the battery?

Lisa
1991 22' LD Multi-Plan
Re: Running fridge when on the road...
Reply #4 –
Hi Lisa. LD  stopped providing the 3 way 'fridge' about 1990, it drew too much power. The modern alternators  put out quite a bit, but the 12vdc operation wasn't very good, even drawing 30+ amps. Propane is the best source while driving. I believe the switch on the dash that LD provided in the '80's would turn off the 12 vdc to the refrigerator, so that you could get gasoline safely. You had to remember to turn it back on (IIRC). Running the 110v AC on the road with an inverter solves the open flame problem in a gas station, but will quickly run your batteries down, so when stopping for groceries, or a nap, or sight seeing nearby you would need to switch to propane anyway. The perceived safety factor of having the tank LPG turned off, is only good if you actually turn it off when driving. And the delivery pipes still have propane in them.
    Most people, including me, drive with the refrigerator running on propane. DO shut it off before getting gas. It only takes someone near you, once, to spill gasoline, and ruin your day. I usually move away from the pumps before restarting the 'fridge'.
    If you are involved in an accident, first thing is turn off the tank outside. I did lose a tire tread in my previous motorhome, which ripped open a gas line. That was near a rear tire. Low pressure doesn't leak very much gas.  I've considered putting a switch, with a reminder light, on the dash to remove all 12v. from the refrigerator. That would shut down the logic board and shut off the gas and flame with it. In case there was an accident involving gasoline or oil on the road. Myself or someone else. I may still do that someday.  RonB 
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Running fridge when on the road...
Reply #5 –
Quote from: RonB  - 
The perceived safety factor of having the tank LPG turned off, is only good if you actually turn it off when driving. And the delivery pipes still have propane in them.

I did a little reading and my thought was just that- I would want to turn off the tank valve itself. But I also wondered about gas in the pipes. I mean, unless you shut off tank and then turn on stove or heater to try and burn off whatever is still in there, I don't see how the pipes would be cleared. I suppose residual gas is safer then having the tank on, but I would think that a blast or fire from the residual gas might be sufficient to blow a hole in the tank anyway.  I'm always an optimist!

I think I'll probably just drive with the tank shut off. 

I'm not clear what the deal is with gasoline and propane, so I'm going to go read about that now.


Lisa
1991 22' LD Multi-Plan
Re: Running fridge when on the road...
Reply #6 –
Lisa-

It is common practice to run the refrigerator on propane when going down the road. As "RonB" said, shut it off before fueling, and turn it back on afterwards. I try to wait until I hear the burner successfully "fire up" after I turn it on. If I forget to turn the refrigerator on, it will stay cold for quite a while, if I leave the doors closed.

Mark H
Former owner, 31-foot gas Class A
Former owner, 1997-8 mid-bath
Re: Running fridge when on the road...
Reply #7 –
Quote from: RonB  - 
Hi Lisa. LD  stopped providing the 3 way 'fridge' about 1990, it drew too much power. The modern alternators  put out quite a bit, but the 12vdc operation wasn't very good, even drawing 30+ amps.  

I have a 1995 TK that came with a 3-way fridge.
I run mine on gas when traveling.
I've ran it on 12VDC also while driving with no issues as far as I could tell.
2021 Mid Bath
 
Re: Running fridge when on the road...
Reply #8 –
Is their any law that states you have to turn propane to fridge off while getting gas? I've looked and I can't find one. I think it's probably good practice but I've never done so myself. Someone would have to deliberately shoot gas directly at your refrigerator to have an issue which seems highly unlikely. My only real concern would be if that happened as in some terrorist came up with the idea ::)  I could be held liable. Not that I think this is any real possibility but it's an interesting scenario to contemplate.
Discuss anything with anyone and disagree agreeably. Always be polite and respectful.
Re: Running fridge when on the road...
Reply #9 –
We always ran our '83 in 12V mode while driving. Since it had manual switching, we did not need to worry about turning off propane in a station. However, keeping the alternator belt sufficiently tensioned was an issue. I burned many alternators up before I bought a tension gauge - doing it by feel doesn't cut it with these old Chevys... Night-time was the big problem - running the fridge and the headlights was too much for the alternator to keep up.

Steve
2004 FL
2013 Honda Fit
Re: Running fridge when on the road...
Reply #10 –
Quote from: Sawyer  - 
Is their any law that states you have to turn propane to fridge off while getting gas? I've looked and I can't find one. I think it's probably good practice but I've never done so myself. Someone would have to deliberately shoot gas directly at your refrigerator to have an issue which seems highly unlikely.

Gasoline fumes are what ignite - if you can smell them, they may also reach the lit flame of your fridge. I have seen signs posted in fueling stops that see a lot of RVs. Also, every ferry we have been on requires it. If ignition happens, your rig would be the first casualty, whether or not you can find any written law...

Steve
2004 FL
2013 Honda Fit
Re: Running fridge when on the road...
Reply #11 –
One day or so we turn on the fridge.   Leave it on the whole time we are on the road and while camping.   Only once in about 46,000 miles we turn it off we had to camp one night at a very extreme angle.   Popane is heavier then air.  It will sink to the lowest level available to it.  
Turning off the fridge is more old wife tale then fact.  Folks have watched to many movies were fuel fires look very easy to start.   Throwing a match into a gallon of gas will just put it out.  
personal fine art photo stuff
TF Mack | Flickr
It's all good .......
2014 Twin King
Re: Running fridge when on the road...
Reply #12 –
Quote from: colddog  - 
  Throwing a match into a gallon of gas will just put it out. 

That is unless there is evaporation that has happened and vapors are sitting on the top of the fluid gas.  Then throwing a match into a gallon of gas would ruin your day and a the day of a few of your neighbors
Linda B
Green 2021 RB
2022 Ford Maverick toad
Re: Running fridge when on the road...
Reply #13 –
Quote from: colddog  - 
One day or so we turn on the fridge.   Leave it on the whole time we are on the road and while camping.   Only once in about 46,000 miles we turn it off we had to camp one night at a very extreme angle.   Popane is heavier then air.  It will sink to the lowest level available to it.  
Turning off the fridge is more old wife tale then fact.  Folks have watched to many movies were fuel fires look very easy to start.   Throwing a match into a gallon of gas will just put it out.  
I think people that stop before entering a gas station and turn off their propane are few and far between. I've never once seen any indication of someone doing that on the outside perimeter of a gas station but countless times have seen RVs ahead of or behind me on the road pull right up to the pump just as I do. I'd be curious to know if there's ever even been a documented case of this starting a fire in a gas station. I googled it and can only find fires caused while filling propane tanks but not one caused while getting gas. Gasoline can indeed be dangerous and by design is highly flammable but I'm not convinced the small flame in your refer compartment is a significant risk factor.
Discuss anything with anyone and disagree agreeably. Always be polite and respectful.
Re: Running fridge when on the road...
Reply #14 –
Back to the original question....how long will the refrigerator contents stay cold if it is not actively cooling itself?  Won't it act like a big cooler box and retain the cool for a good 4 or 5 hours without trouble?
Linda B
Green 2021 RB
2022 Ford Maverick toad
Re: Running fridge when on the road...
Reply #15 –
Quote from: LindaB  - 
Back to the original question....how long will the refrigerator contents stay cold if it is not actively cooling itself?  Won't it act like a big cooler box and retain the cool for a good 4 or 5 hours without trouble?
Depends on outside temperature. If it's cool out you can drive all day with refer off but if it's 100 degrees it starts warming almost immediately. I had problems with my camper refer blowing out so I used to turn it off and have some experience with that method. Then there's trips to the fridge for cold drinks and lunch break which entail opening the fridge which also makes it lose it's cool.
Discuss anything with anyone and disagree agreeably. Always be polite and respectful.
Re: Running fridge when on the road...
Reply #16 –
Quote from: Steve  - 
. I burned many alternators up before I bought a tension gauge - doing it by feel doesn't cut it with these old Chevys... Night-time was the big problem - running the fridge and the headlights was too much for the alternator to keep up.

Our experience with our old 1983 LD was the same as Steves, the alternator could keep up with the electrical needs when the headlights or the dash A/C was on.  With both A/C and headlight on, the battery would die in a couple hours.
I built new brackets for the engine and install a 150-amp alternator, enabling the battery to stay charged under all operating conditions.  Our refrigerator needed to manually be put into 12-volt mode and would stay there, no matter is the engine was running. One time I forgot to switch it and killed the battery.
 Since then, about 24 years ago, we have alway run the refrigerator on propane.
If you are worried about a mass gas release, newer propane tanks have a flow control valve that shuts the propane off if the flow rate is higher than normal, in case a propane line breaks.

A cold refrigerator will stay that way for a while, how long depends on how high the ambient temperature is.
A few hours at best, don't push it too far, food poisoning may come calling.
Most folks eventually get over their fear of fire and run with the propane on. I have never heard of an LD burning, while on the road.


Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Running fridge when on the road...
Reply #17 –
My fridge stays cold a good while. I have a temp sensor to an indoor/outdoor thermometer in the fridge and the reading unit in a cup holder so I can watch the temp of the fridge.  I have forgotten to turn the fridge back on and noticing the temp creeping up saved my food. 
The indoor outdoor thermometer is avable at most any hardware store.
Currently: 2008 36' Tiffin Open Road
Previously: 2007 Mid Bath
Re: Running fridge when on the road...
Reply #18 –
Quote from: LindaB  - 
Back to the original question....how long will the refrigerator contents stay cold if it is not actively cooling itself?  Won't it act like a big cooler box and retain the cool for a good 4 or 5 hours without trouble?

If the fridge is crammed full of cold items, they act as a thermal sink with a large mass. Warming up that mass will take a lot longer than with a lightly-loaded box. If the fridge is to be off for a lengthy time, adding ice first will help - much as adding ice to a cooler. The freezer should be tightly packed with frozen food too. Still, thermal conduction of heat into the box via warmed up cooling unit from outside heat makes the fridge less thermally efficient when turned off than a cooler box.

Steve


Steve
2004 FL
2013 Honda Fit
Re: Running fridge when on the road...
Reply #19 –
Norcold still makes a 3-way fridge and its still standard in some RV's.  I asked the local dealer about why they were still making a 3-way.  He said it was basically convenience.  The ability to use three different power sources.  The DC amp draws are a little lower on the newer models.  Battery technology and the super output alternators let them run more efficiently.

A lot of RV manufactures are going with the newer compressor driven AC/DC fridges.  Norcold, Dometic, and Nova-Kool are the most popular models.  They only draw 3.2-5.0 DC amps.  Because of their superior cooling, the "duty cycle" is even less power consumption.  With the advent of solar and high performance batteries like AGM's makes this all possible.  After 12-18 months on these installations, the reports have been very positive so far.  The newer 220-330 amp AGM banks and solar seem to be keeping up with the power consumption.

We have been using compressor driven fridges (Nova-Kool) for the last 20 years on our boats.  They have performed very well.  We dont have solar or a gen set, but a very large house bank with smart charging system.
2003 MB
Re: Running fridge when on the road...
Reply #20 –
I very rarely turn off my fridge when making a fuel stop, in fact there have been times when I have not turned the fridge off when taking on propane.

One factor I take into account is that my fridge is located on the patio side of the rig, while the fuel inputs are both on the opposite side. It would take extraordinary conditions to have fuel fumes or vapor reach the opposite side of the coach in a quantity to cause ignition.   ::) 
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!
Re: Running fridge when on the road...
Reply #21 –
Quote from: Sawyer  - 
I think people that stop before entering a gas station and turn off their propane are few and far between. I've never once seen any indication of someone doing that on the outside perimeter of a gas station but countless times have seen RVs ahead of or behind me on the road pull right up to the pump just as I do. I'd be curious to know if there's ever even been a documented case of this starting a fire in a gas station. I googled it and can only find fires caused while filling propane tanks but not one caused while getting gas.
Before pulling up to the gas pump I turn off the fridge from the inside.  What I was told was one doesn’t want to have the igniter doing it’s job while pumping gas. Akin to not lighting a cigarette while at the pump.  While the odds might be low, my thought is why push it.  The trick is to remember to turn the fridge back on after leaving.

For several years I have been using an Acu-Rite digital thermometer with two sensors. The idea was one in fridge and one in freezer. Been using it at home as well as in the Lazy Daze and have ended up only using sensor in the fridge.  It is nice to be able to see temp without opening the door.  Overtime one gets a sense of how the temp changes when door is opened, if sun is hitting fridge side of rig and need to raise/lower setting based on outside temperature.

We also use one of the little battery powered fans to help with airflow.

2005 Island Bed, Hyundai Accent
Re: Running fridge when on the road...
Reply #22 –
"...in fact there have been times when I have not turned the fridge off when taking on propane."
----
Steve, I'm very surprised that any propane dealer/supplier would fill an onboard LPG tank if any appliance was running! This is always the first question that I'm asked when I take on propane, even at my regular fill place with the same pumper. If the gas pump or the propane pump is running around my rig, every "flame" is shut down!

IMO, having an open flame anywhere near LPG vapor or gasoline vapors or any other volatile substance is way more of a crapshoot than I ever want to take.  :o

2003 TK has a new home
Re: Running fridge when on the road...
Reply #23 –
"I think people that stop before entering a gas station and turn off their propane are few and far between. I've never once seen any indication of someone doing that on the outside perimeter of a gas station but countless times have seen RVs ahead of or behind me on the road pull right up to the pump just as I do."
---
Maybe many don't, but "people" do a whole lot of things that aren't necessarily smart.

2003 TK has a new home
Re: Running fridge when on the road...
Reply #24 –
Quote from: Joan  - 

---
Maybe many don't, but "people" do a whole lot of things that aren't necessarily smart.




Like driving down the road at 60mph with people driving the other direction going 60mph and only a few feet of air between them ? LOL
Someday people will look back at things we do today and think holy cow those people were insane. Not only did they do that but they continued to do it after waiting for hours for bodies and scrap metal to be removed from their path due to one of these close encounters that ended badly. I often think driving is not too smart and I should limit it to only when absolutely necessary but as I type this I'm gathering stuff together for a 3000 mile round trip to the desert. ;D
Having said that now that I'm retired I don't drive in winter unless the roads are good and feel bad for all those working people that have to get to the job on time no matter how bad the roads are. Seems like every time we have a big ice or snowstorm somebody dies around here on their way to or from work. We have a friend who's an ER nurse, they callously call it winter kill.
Discuss anything with anyone and disagree agreeably. Always be polite and respectful.